Using a medium saucepan, add half-and-half and place over medium-low heat. Heat, stirring occasionally, until half-and-half just begins to simmer.

Meanwhile, using a separate bowl, whisk together the sugar and egg yolks until well blended.

Gradually pour the heated half-and-half into the egg yolk mixture; whisking vigorously the entire time.

Transfer this mixture back into the saucepan and cook over medium-low heat, stirring constantly, until custard thickens noticeably and coats a wooden spoon. (~4-6 minutes).

Once the custard mixture has thickened, remove from heat and add the heavy cream; stir until well combined.

Pour mixture through a fine-mesh strainer into a clean container.

Add cream cheese, vanilla, cinnamon, ginger and nutmeg. Using a hand mixer, beat until well combined. (Note: If a few small pieces of cream cheese remain, don’t worry!)

Cover with plastic wrap, pressing the plastic directly onto the surface of the mixture, and refrigerate at least 3 hours, or preferably overnight.

Using a small saucepan, add butter and brown sugar; place over medium heat. Heat, stirring occasionally until both butter and brown sugar have melted.

Add grated carrots and raisins; stir until well combined. Continue cooking, stirring occasionally, for 4-5 minutes. Remove from heat and let cool to room temperature.

Stir carrot/raisin mixture and chopped walnuts into the chilled ice cream base mixture.